Membrane separation devices, systems and methods employing same, and data management systems and methods

ABSTRACT

A membrane separation device is disclosed along with systems and methods employing the device in blood processing procedures. In one embodiment, a spinning membrane separator is provided in which at least two zones or regions are created in the gap between the membrane and the shell, such that mixing of the fluid between the two regions is inhibited by a radial rib associated with the membrane that decreases the gap between the membrane and the shell to define two fluid regions, the ridge isolating the fluid in the two regions to minimize mixing between the two. Automated systems and methods are disclosed for separating a unit of previously collected whole blood into components, such as concentrated red cells and plasma, for collecting red cells and plasma directly from a donor in a single pass, and for cell washing. Data management systems and methods and priming methods are also disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing dates of U.S.Provisional Application Ser. Nos. 61/451,903, filed Mar. 11, 2011,61/537,856, filed Sep. 22, 2011, 61/538,558, filed Sep. 23, 2011, and61/550,516, filed Oct. 24, 2011, the entire contents of each beingincorporated herein by reference.

FIELD OF THE DISCLOSURE

The present application is related, in part, to separation devices ofthe type employing relatively rotating surfaces, at least one of whichcarries a membrane for filtering a component from fluid passed betweenthe surfaces; to fluid flow circuits and systems incorporating such aseparator; and to the use of such systems to separate biological cells,such as red cells, plasma or white cells, from whole blood, a storagemedium, a suspension medium, a supernatant, or the like.

BACKGROUND

Traditional blood collection continues to rely heavily on manualcollection of whole blood from healthy donors through blood drives, fromdonor visits to blood centers or hospitals and the like. In typicalmanual collection, whole blood is collected by simply flowing it, underthe force of gravity and venous pressure, from the vein of the donorinto a collection container. The amount of whole blood drawn istypically a “unit,” which is about 450 ml.

More specifically, such a collection typically employs a pre-assembledarrangement of tubing and containers or bags, including a flexibleplastic primary container or bag for receiving a unit of whole bloodfrom a donor and one or more “satellite” containers or bags. The bloodis first collected in the primary container, which also contains ananticoagulant (typically containing sodium citrate, phosphate anddextrose—often referred to as CPD). A preservative (often called an“additive solution” or AS, and commonly containing a saline, adenine andglucose medium—which is referred to as SAG) may be included as part of alarger assembly of bags and tubes that are used in processing after theblood is collected.

After collection of a unit of whole blood, it is common practice inblood banking to transport the unit of whole blood, with connectedtubing and containers, to a blood component processing laboratory,commonly referred to as a “back lab,” for further processing. Furtherprocessing usually entails manually loading the primary container andassociated tubing and satellite containers into a centrifuge to separatethe whole blood into components such as concentrated red cells andplatelet-rich or platelet-poor plasma. These components are thenmanually expressed from the primary container into other pre-connectedsatellite containers, and may be again centrifuged to separate theplatelets from plasma. Subsequently, the blood components may beleukoreduced by filtration for further processing or storage. In short,this process is time consuming, labor intensive, and subject to possiblehuman error.

Another routine task performed by blood banks and transfusion center is“cell washing.” This may be performed to remove and/or replace theliquid medium (or a part thereof) in which the cells are suspended, toconcentrate or further concentrate cells in a liquid medium, and/or topurify a cell suspension by the removal of unwanted cellular or othermaterial.

Previous cell washing systems most typically involved centrifugation ofa cell-suspension, decanting of the supernatant, re-suspension ofconcentrated cells in new media, and possible repetition of these stepsuntil the cells of the suspension are provided at an adequately high orotherwise desirable concentration. Centrifugal separators used in theprocessing of blood and blood components have commonly been used in suchcell-washing methods.

These processes are also quite time consuming, requiring repeated manualmanipulation of the blood or blood components and assembly ordisassembly of various fluid processing apparatus. This, of course,increases not only the costs, but the potential for human error ormistake. Accordingly, despite decades of advancement in blood separationdevices and processes, there continues to be a desire for better and/ormore efficient separation devices, systems and methods applicable tobasic blood collection and processing modalities.

While many of the prior blood separation apparatus and procedures haveemployed centrifugal separation principles, there is another class ofdevices, based on the use of a membrane, that has been used forplasmapheresis, that is separating plasma from whole blood. Morespecifically, this type of device employs relatively rotating surfaces,at least one or which carries a porous membrane. Typically the deviceemploys an outer stationary housing and an internal spinning rotorcovered by a porous membrane.

One such well-known plasmapheresis device is the Autopheresis-C®separator sold by Fenwal, Inc. of Lake Zurich, Ill. A detaileddescription of a spinning membrane separator may be found in U.S. Pat.No. 5,194,145 to Schoendorfer, which is incorporated by referenceherein. This patent describes a membrane-covered spinner having aninterior collection system disposed within a stationary shell. Blood isfed into an annular space or gap between the spinner and the shell. Theblood moves along the longitudinal axis of the shell toward an exitregion, with plasma passing through the membrane and out of the shellinto a collection bag. The remaining blood components, primarily redblood cells, platelets and white cells, move to the exit region betweenthe spinner and the shell and then are typically returned to the donor.

Spinning membrane separators have been found to provide excellent plasmafiltration rates, due primarily to the unique flow patterns (“Taylorvortices”) induced in the gap between the spinning membrane and theshell. The Taylor vortices help to keep the blood cells from depositingon and fouling or clogging the membrane.

While spinning membrane separators have been widely used for thecollection of plasma, they have not typically been used for thecollection of other blood components, specifically red blood cells.Spinning membrane separators also have not typically been used for cellwashing. One example of a spinning membrane separator used in thewashing of cells such as red blood cells is described in U.S. Pat. No.5,053,121 which is also incorporated by reference in its entirety.However, the system described therein utilizes two separate spinnersassociated in series or in parallel to wash “shed” blood of a patient.Other descriptions of the use of spinning membrane separators forseparation of blood or blood components may also be found in U.S. Pat.Nos. 5,376,263; 4,776,964; 4,753,729; 5,135,667 and 4,755,300.

The subject matter disclosed herein provides further advances inmembrane separators, potential cost reduction and various other advancesand advantages over the prior manual collection and processing of blood.

SUMMARY OF THE DISCLOSURE

The present subject matter has a number of aspects which may be used invarious combinations, and the disclosure of one or more specificembodiments is for the purpose of disclosure and description, and notlimitation. This summary highlights only a few of the aspects of thissubject matter, and additional aspects are disclosed in the drawings andthe more detailed description that follows.

In accordance with one aspect of the disclosure, a method for priming amembrane separator is provided. The membrane separator comprises ahousing with a top and a bottom, with at least one port adjacent each ofthe top and the bottom of the housing, with the membrane disposed withinthe housing so as to spin about a generally vertically-oriented axis.The method for priming includes introducing a priming fluid through theport adjacent the bottom of the housing, and then flowing additionalpriming fluid through the port adjacent the bottom of the housing sothat a priming fluid-air interface is formed that advances upwardlythrough the housing to displace air within the housing and to expel theair through the port adjacent the top of the housing, whilesimultaneously wetting the membrane. Additional priming fluid continuesto be flowed through the port adjacent the bottom of the housing untilthe priming fluid-air interface has advanced vertically across theentire membrane. The priming fluid may comprise either a low-viscosity,non-biological fluid, or whole blood.

In accordance with another aspect of the disclosure, a fluid processingcircuit is provided comprising a separator including relatively rotatingsurfaces within a housing in which at least one of which surfacescarries a porous membrane, and the surfaces are spaced apart to define agenerally axially extending gap therebetween. The housing includes atleast one fluid inlet and at least one fluid outlet communicatingdirectly or indirectly with the gap, with the outlet being located at alower region of the housing and the inlet being located at a region ofthe housing spaced axially upwardly from the outlet. The housingpreferably has an upper end and a lower end in an operating position,with the inlet is proximate to the upper end and the outlet proximate tothe lower end. The processing circuit further comprises a source ofpriming fluid and a conduit connecting the source of priming fluid tothe at least one outlet of the housing.

Additionally, the processing circuit may preferably comprise a rotordisposed within the housing, with the outer surfaces of the rotor beingspaced from an inner surface of the housing to define an annular gaptherebetween. The membrane separator and housing are preferablyrelatively rotatable to one another about a generally-vertical axis, andthe at least one outlet communicates directly with the gap between themembrane and the housing. The fluid inlet preferably communicates withthe gap for delivering a fluid containing blood or blood components intothe gap, and at least one of the outer surface and inner surfacecarrying a porous membrane, with the fluid outlet communicating directlywith the gap or with a side of the membrane facing away from the gap orwith both.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the present subject matter are described inthe following detailed description and shown in the attached figures, ofwhich:

FIG. 1 is a perspective view a spinning membrane separator, in partialcross section and with portions removed to show detail.

FIG. 2 is a longitudinal cross sectional view of the spinning membraneseparator of FIG. 1.

FIG. 3 is a contour plot of outlet hematocrit and outlet wall shearstress as a function of relative filtration length and spinner radiusbased on a theoretical design model.

FIG. 4 is a contour plot of outlet hematocrit and outlet plasmahemoglobin concentration as a function of relative filtration length andspinner radius based on a theoretical design model for which themembrane tangential velocity is constant.

FIG. 5 is a contour plot of outlet hematocrit and Taylor number as afunction of relative filtration length and spinner radius based on atheoretical design model.

FIG. 6 is a three-dimensional plot of plasma hemoglobin concentration asa function of relative filtration length and spinner radius based on atheoretical design model.

FIG. 7 is a perspective view of a spinning membrane device or separatoraccording to the present application.

FIG. 8 is a schematic cross sectional view of a spinning membraneseparator in accordance with the present application in which thespinner includes a radially-extending ridge for defining separate fluidregions.

FIG. 9 is a schematic view of an automated whole blood separation systemfor processing previously-collected whole blood including a disposablefluid flow circuit module and a durable controller or control modulewith the fluid flow circuit module assembled thereon.

FIG. 10 is a flow diagram showing one embodiment of fluid flow through afluid flow circuit as described herein for processing a unit of wholeblood into a concentrated red cell product and a plasma product.

FIG. 11 is similar to FIG. 9 but a somewhat more detailed view ofcomponents of a disposable fluid flow circuit or module and a durablecontroller module.

FIG. 12 is a schematic view of an alternate embodiment of the systemaccording to the present disclosure in which the system is used for theseparation of previously-collected whole blood.

FIG. 12A is a schematic view of a further alternate embodiment, similarto FIG. 12.

FIG. 13 is a perspective view of a two-pump blood separation system suchas that shown in FIGS. 9, 11, 12 and 12A.

FIG. 14 is a schematic view of a further alternative similar to FIG. 12,except incorporating three pumps, illustrating the system in the primingphase.

FIG. 15 is a schematic view of the system of FIG. 14 illustrating thesystem in the separation phase.

FIG. 15A is a schematic view of a further alternative three-pump system,similar to FIGS. 14 and 15.

FIG. 16 is a schematic view of an automated whole blood collectionsystem according to the present disclosure showing the configuration ofthe system for automated chairside collection and processing of wholeblood from a donor in the priming mode.

FIG. 17 is a schematic view of the system of FIG. 16 showing theconfiguration of the system for collecting and separating whole bloodinto red blood cells and plasma.

FIG. 18 is a schematic view of the system of FIG. 16 showing theconfiguration of the system for rinsing the system with anticoagulantafter the completion of blood collection from the donor.

FIG. 19 is a schematic view of the system of FIG. 16 showing theconfiguration of the system at the end of the blood collectionprocedure.

FIG. 20 is a schematic view of the system of FIG. 16 showing theconfiguration of the system in the optional arrangement for filteringthe collected red blood cells through a leukocyte filter.

FIG. 21 is a schematic view of an alternate embodiment of an automatedwhole blood collection system to that of FIGS. 16-20 in which thesingle-use disposable fluid circuit component comprises an integralleukoreduction filter as part of the draw line of the donor accessdevice.

FIG. 22 is a schematic view of an alternative embodiment of thesingle-use disposable fluid circuit of FIG. 21 in which theleukoreduction filter is positioned in the draw line downstream from theentry point where anticoagulant is introduced into the whole blood.

FIG. 23 shows a disposable set useful in the washing of cells inaccordance with the method disclosed herein.

FIG. 24 shows another embodiment of a disposable set useful in thewashing of cells in accordance with an alternative method disclosedherein.

FIG. 25 shows an embodiment of the control panel of a device useful inthe washing of cells in accordance with the method disclosed herein.

FIGS. 26-28 are flowcharts of the steps in the method cell washingdisclosed herein.

FIG. 29 is a flow chart illustrating a data management method inaccordance the present disclosure.

FIG. 30 is a schematic drawing of a data management system according tothe present disclosure in combination with a collection container and aprocessing kit.

FIG. 31 is a flow chart illustrating the various steps comprising amethod for data management in accordance with the present disclosure.

DETAILED DESCRIPTION

A more detailed description of the spinning membrane separator inaccordance with the present disclosure and its use in various automatedsystems is set forth below. It should be understood that descriptionbelow of specific devices and methods is intended to be exemplary, andnot exhaustive of all possible variations or applications. Thus, thescope of the disclosure is not intended to be limiting, and should beunderstood to encompass variations or embodiments that would occur topersons of ordinary skill.

Turning to FIGS. 1 and 2, a spinning membrane blood separation orfractionation system, generally designated 10, is shown. Such a system10 is typically used to extract plasma from whole blood obtained from anindividual human donor. For ease of understanding, only the plasmaseparation device and the associated drive unit are shown, although itshould be understood that such a separator forms part of a disposablesystem including collection bags, bags of additives such as saline orACD, return bags, tubing, etc., and that there are also associatedcontrol and instrumentation systems for operation of the device.

The system 10 includes a generally cylindrical housing 12, mountedconcentrically about a longitudinal vertical central axis. An internalmember 14 is mounted concentric with the central axis. The housing andinternal member is relatively rotatable. In the preferred embodiment, asillustrated, the housing is stationary and the internal member is arotating spinner that is rotatable concentrically within the cylindricalhousing 12. The boundaries of the blood flow path are generally definedby the gap 16 between the interior surface of the housing 12 and theexterior surface of the rotary spinner 14. The spacing between thehousing and the spinner is sometimes referred to as the shear gap. Atypical shear gap may be approximately 0.025-0.050 inches (0.067-0.127cm) and may be of a uniform dimension along the axis, for example, wherethe axis of the spinner and housing are coincident. The shear gap mayalso vary circumferentially for example, where the axis of the housingand spinner are offset.

The shear gap also may vary along the axial direction, for examplepreferably an increasing gap width in the direction of flow to limithemolysis. Such a gap width may range from about 0.025 to about 0.075inches (0.06-0.19 cm). For example the axes of the housing and rotorcould be coincident and the diameter of the rotor decrease in the axialdirection (direction of flow) while the diameter of inner surface of thehousing remains constant or the diameter of the housing increases whilethe rotor diameter remains constant, or both surfaces vary in diameter.For example the gap width may be about 0.035 inches (0.088 cm) at theupstream or inlet end of the gap and about 0.059 inches (0.15 cm) at thedownstream end or terminus of the gap. The gap width could be varied byvarying the outer diameter of the rotor and/or the inner diameter of thefacing housing surface. The gap width could change linearly or stepwiseor in some other manner as may be desired. In any event, the widthdimension of the gap is preferably selected so that at the desiredrelative rotational speed, Taylor-Couette flow, such as Taylor vortices,are created in the gap and hemolysis is limited.

Whole blood is fed from an inlet conduit 20 through an inlet orifice 22,which directs the blood into the blood flow entrance region in a pathtangential to the circumference about the upper end of the spinner 14.At the bottom end of the cylindrical housing 12, the housing inner wallincludes an exit orifice 34.

The cylindrical housing 12 is completed by an upper end cap 40 having anend boss 42, the walls of which are nonmagnetic, and a bottom endhousing 44 terminating in a plasma outlet orifice 46 concentric with thecentral axis.

The spinner 14 is rotatably mounted between the upper end cap 40 and thebottom end housing 44. The spinner 14 comprises a shaped central mandrelor rotor 50, the outer surface of which is shaped to define a series ofspaced-apart circumferential grooves or ribs 52 separated by annularlands 54. The surface channels defined by the circumferential grooves 52are interconnected by longitudinal grooves 56. At each end of themandrel 50, these grooves 56 are in communication with a central orificeor manifold 58.

In the illustrated embodiment, the surface of the rotary spinner 14 isat least partially, and is preferably substantially or entirely, coveredby a cylindrical porous membrane 62. The membrane 62 typically has anominal pore size of 0.6 microns, but other pore sizes may alternativelybe used. Membranes useful in the washing methods described herein may befibrous mesh membranes, cast membranes, track etched membranes or othertypes of membranes that will be known to those of skill in the art. Forexample, in one embodiment, the membrane may have a polyester mesh(substrate) with nylon particles solidified thereon, thereby creating atortuous path through which only certain sized components will pass. Inanother embodiment, the membrane may be made of a thin (approximately 15micron thick) sheet of, for example, polycarbonate. In this embodiment,pores (holes) may be larger than those described above. For example,pores may be approximately 3-5 microns. The pores may be sized to allowsmall formed components (e.g., platelets, microparticles, etc.) to pass,while the desired cells (e.g., white blood cells) are collected.

The rotary spinner is mounted in the upper end cap to rotate about a pin64, which is press fit into the end cap 40 on one side and seated withina cylindrical bearing surface 65 in an end cylinder 66 forming part ofthe rotary spinner 14. The internal spinner or outer housing may berotated by any suitable rotary drive device or system. As illustrated,the end cylinder 66 is partially encompassed by a ring 68 of magneticmaterial utilized in indirect driving of the spinner 14. A drive motor70 exterior to the housing 12 is coupled to turn an annular magneticdrive member 72 that includes at least a pair of interior permanentmagnets 74. As the annular drive member 72 is rotated, magneticattraction between the ring 68 interior to the housing 12 and themagnets 74 exterior to the housing locks the spinner 14 to the exteriordrive, causing the spinner 14 to rotate.

At the lower end of the rotary spinner 14, the central outlet orifice 58communicates with a central bore 76 in an end bearing 78 that isconcentric with the central axis. An end bearing seat is defined by aninternal shoulder 80 that forms a lower edge of a central opening 82.The central opening 82 communicates with the plasma outlet orifice 46.If the inner facing surface of the housing is covered entirely orpartially by a membrane, a fluid collection or manifold may be providedbeneath the membrane to collect plasma and direct it through a housingoutlet (not shown).

I. Membrane Separator Design

In keeping with one aspect of the application, a spinning membraneseparator is provided that provides for improved plasma flow rates withan acceptably low level of hemolysis in the retained blood. Variousfactors are known to affect the filtration flow rate through spinningmembrane separators, including the speed of rotation, the size of thegap between the spinning membrane and the shell, the effective area ofthe membrane, the concentration of red blood cells (or hematocrit), andthe blood viscosity. Previous practices in the design of spinningmembrane devices have been largely empirical, aided to some extent byvague phenomenological descriptions of the effects of the various designparameters on performance and hemolysis. This has proved to beinefficient in terms of development time and technical resources spent.

In contrast, the parameters of the spinning membrane separator of thepresent application were determined based on quantitative differentialmodels that take into account the local plasma velocity through themembrane and the local hemoglobin concentration. These differentialmodels were integrated over the length of the device to provide a totalplasma flow rate and plasma hemoglobin concentration at the outlet ofthe device.

The method included the operational inputs based upon the existingPlasmacell-C separator geometry and operating conditions, includingdonor hematocrit, inlet blood flow rate, rotational speed, and effectivemembrane area. Also factored in were the geometric inputs of rotorradius, the width of the annular gap, and the length over which theintegration is performed. See Table 1 below. To obtain predicted valuesfor hypothetical separators, rotor radius and filtration length werevaried from about 1.0 to up to about 2.0 times the current Plasmacell-Cvalues in increments of 0.05, providing a 21×21 design space grid foreach output variable of interest. For all devices, the housing taper andthe gap at the outlet were held constant, and the inlet gap androtational speed were varied accordingly. Models were also developedwhich related blood viscosity and density to hematocrit, temperature,and anticoagulant concentration.

TABLE 1 Inputs for Model Calculations Parameter, units Value Inlet bloodflow rate, ml/min 106 Inlet hematocrit, % 42 Temperature, ° C. 35Citrate concentration, % 5.66 Filtration length, in 2.992 Rotor radiuswith membrane, in 0.5335 Inlet gap, in 0.0265 Outlet gap, in 0.0230Effective membrane fraction 0.50 Width of membrane bonding area, in 0.18Rotation speed, rpm 3600 Wall hematocrit, % 0.90 Red cell radius, μm2.75 Red cell hemoglobin concentration, 335.60 mg/dL Density of plasma,g/cm³ 1.024 Density of packed red cells, g/cm³ 1.096 Viscosity ofcitrated plasma, cP 1.39

In one implementation of the method, outputs of plasma flow rate andhemoglobin concentration were obtained for various values of the rotorradius, the rotational speed, and the integration length. The results ofthe models are shown in superimposed contour plots of the outlethematocrit and outlet wall shear stress (FIG. 3), the outlet hematocritand the outlet plasma hemoglobin concentration (FIG. 4), and the outlethematocrit and Taylor number (FIG. 5), all as a function of the relativefiltration length and spinner radius. As used herein, “filtrationlength” is understood to be axial length of the central mandrel or rotor50 from the beginning to the end of grooves or ribs 52. It generallyrepresents the length of the membrane available for filtration. The“spinner radius” or “spinner diameter” is understood to be the radius ordiameter of the rotor with the membrane attached. FIG. 6 shows theplasma hemoglobin results as a function of filtration length and spinnerradius in a three-dimensional plot, showing the increase in hemoglobinwith larger devices. These results were then evaluated to provide thebest balance of high plasma flow rate with acceptably low levels ofhemolysis.

The models indicated that the effective area of the membrane has thestrongest positive influence on performance. Further, while increasingthe membrane area by increasing the diameter of the rotor morepositively impacts flow rates than increasing the membrane area byincreasing the length of the rotor, it also increases the potential forhemolysis due to the increased velocity of the membrane, and thus theincrease in shear forces in the gap.

Accordingly, the models predicted lengths and diameters for the rotorthat would result in increased membrane areas whose use would also haveacceptably low levels of hemolysis. Prototype separators (based on theresults of the models) were made and tested to validate the resultspredicted by the models. Table 2, below, compares a current Plasmacell-Cplasmapheresis device with two potential alternatives based on themodels.

TABLE 2 Device Parameter, units Plasmacell-C RL 140-162 RL 140-185Relative filtration length 1.00 1.62 1.85 Relative spinner radius 1.001.40 1.40 Relative spinner speed 1.00 0.70 0.75 Filtration length, in2.992 4.847 5.535 Spinner radius, in 0.5335 0.7469 0.7469 Spinner speed,rpm 3600 2520 2700 Inlet gap, in 0.0265 0.0287 0.0295 Outlet gap, in0.0230 0.0230 0.0230 Inlet flow rate, ml/min 106 106 106 Inlethematocrit, % 42 42 42 Citrate concentration, % 5.66 5.66 5.66 Plasmaflow rate. ml/min 36.33 47.42 50.57 Outlet hematocrit, % 63.90 76.0080.32 Outlet plasma hemoglobin 5.04 14.36 27.84 concentration, mg/dLResidence time, s 2.98 7.99 9.77 Centripetal pressure, mmHg 100.22 96.25110.50 Torque, in-oz 1.48 4.70 6.29 Outlet Taylor number 89.07 51.0046.96

With reference to Table 2 and FIG. 7, a spinning membrane separator 10includes a rotary spinner 14 which has a spinner diameter D, afiltration length FL, and an overall length LOA. In a typicalplasmapheresis device, such as the Plasmacell-C separator, the rotor hasa diameter D of approximately 1.1″, a filtration length FL, ofapproximately 3″, and an overall length, LOA, of approximately 5.0″.

In accordance with the present application, it has been found that thediameter of the membrane can be increased by up to about 2.0 times thediameter of the membrane found in a typical plasmapheresis device, whilethe length can be increased up to about 2.5 times the length of thespinning membrane in a typical plasma pheresis device. An increase inthe rotor size within these perimeters increases the filter membranearea sufficient to provide for a high plasma flow rate, while providingfor an acceptably low level of hemolysis. In a specific example, aspinning membrane separator according to the present application mayadvantageously have a diameter D of 1.65″, a filtration length FL of5.52″, and an overall length LOA of 7.7″.

Prototype spinning membrane separators were tested with bovine and humanblood to validate the results predicted by the models. Blood flow ratesof 100 ml/min were obtained with spinner speeds varying from 1000-3500rpm. Outlet hematocrit levels of 80% and higher were obtained beforehigh levels of fouling of the membrane were experienced. Collectiontimes for 880 ml of plasma ranged from between approximately 18 and 20minutes.

As noted above, the residence time of the red blood cells in the sheargap has a direct relationship to the amount of hemolysis. In spinningmembrane separation devices, flow regions exist along the axial lengthof the rotor where the fluid flows is relatively stagnant, resulting inpockets of hemolysis. To the extent that red blood cells from the highhemolysis region intermix with the flow in the low hemolysis region, thequality of the collected red blood cells is degraded.

Accordingly, in keeping with another aspect of the application, a methodis provided for creating separate fluid flow regions in the gap of aspinning membrane separator without the use of seals. The separate flowregions reduce or minimize the influence of mixing of the fluids betweenthe two flow regions. The separate flow regions are achieved by having araised rib or ridge in the gap to reduce or minimize the gap between thespinner and the outer cylinder. Preferably, the ridge or rib is providedon the surface of the rotor beyond where the spinning membrane isattached thereto.

The ridge is preferably located so as to define the boundary of the highperfusion flow region. The radial size of the ridge is inverselyproportional to the decree of mixing allowed between the two regionsdefined thereby, with a larger radial dimension for the ridge allowingfor less mixing. The axial dimension or extent of the ridge is alsoinversely proportional to the degree of mixing allowed, with a largeraxial dimension allowing for less mixing. The axial dimension of theridge is preferably at least one gap-size long to minimize the formationof adjacent Taylor vortices causing unwanted mixing.

With reference to FIG. 8, a schematic cross sectional representation ofa spinning membrane separation device 10 is shown. The device comprisesa fixed outer cylinder 12 and a rotating inner cylinder 14 having afilter member carried thereon. In accordance with the presentapplication, the inner cylinder is provided with a radial ridge 90. Thisridge serves to divide the gap 16 between the spinner and the outerhousing into two fluid regions. A first fluid region 92 has a stagnant,non-perfused region of flow, typically on the portion of the spinnerthat extends beyond the filter membrane. A second fluid region 94, whichtypically contacts the filter membrane, has a highly perfused region offlow.

Because the first fluid region 92 is not perfused, blood residingtherein is exposed to increased shear stresses for longer periods oftime than the blood in the second fluid region 94. Thus, the blood inthe first fluid region 92 may often become hemolyzed and has highconcentrations of free hemoglobin (Hb). The ridge 90 inhibits fluid flowbetween the two fluid regions, thus minimizing the extent of mixing ofthe Hb-contaminated blood in the first region 92 with the low Hb bloodin the second region 94.

While the ridge 90 is shown as being integral with the rotor, it couldalso be formed on the inside of the outer cylinder to achieve the sameeffect. As noted above, the axial dimension of the ridge should be atleast one-gap size long. A typical spinning membrane separation devicefor performing plasmapheresis typically has a gap between the spinnerand the containment wall of from 0.023″ to 0.0265″, and a ridge inaccordance with the present application could have an axial dimensionwithin the same general range. However, larger axial dimensions for theridge will result in reduced mixing and, in one example, a rotor havinga radially-extending ridge with an axial dimension of 0.092″ has beenfound to be effective.

II. Systems and Methods for Processing Previously Collected Whole Blood

A spinning membrane separation device as described above may beadvantageously used in various blood processing systems and methods forwhich prior devices generally were not suited, particularly systems andprocess for obtaining Red Blood Cells. In one type of system and method,the spinner may be used for “back lab” processing of previouslycollected whole blood, as shown in FIGS. 9-15A.

Turning now to FIG. 9, a disposable fluid flow circuit or module A and areusable durable controller or module B configured to cooperate with andcontrol flow through the fluid circuit A are schematically illustrated.The disposable fluid circuit A as illustrated in FIG. 9 includes variouscomponents interconnected by flexible plastic tubing defining flow pathsbetween the components. The circuit is preferably fully pre-assembledand pre-sterilized with the possible exception of the unit of wholeblood container and the cell preservative container. More specifically,the illustrated disposable circuit in FIG. 9 includes whole bloodcontainer 101, a cell preservation solution container 102, bloodcomponent separator 108, plasma collection container 112, optionalleukocyte reduction filter 113, and red cell collection container 115.While not illustrated in FIG. 9, the reusable module B may have hangerswith associated weigh scales for supporting any or all of the containers101, 102, 112 and 115. In various of the other embodiments discussedherein, such hangers/weigh scales may not be illustrated, but areunderstood to be part of the described systems.

The whole blood collection container 101 may be any suitable containerbut is typically a flexible plastic pouch or bag in which approximately450 ml of whole blood have been previously collected. The container 101may be part of a separate system during collection and then joined tothe rest of the fluid circuit A or actually part of the circuit A at thetime of collection. At the time collection, in accordance with customaryprocedure, the whole blood is mixed with an anticoagulant located in theprimary container to prevent premature coagulation. Accordingly, “wholeblood” as used herein includes blood mixed with anticoagulant.

Flexible plastic tubing 105 is attached to the whole blood collectioncontainer, such as by a sterile connection device or other suitableattachment mechanism, and defines a whole blood fluid flow path betweenthe whole blood container 101 and a junction with cell preservativesolution tubing 103, which extends from the cell preservation solutioncontainer 102 to the flow path junction. The flow path junction betweenthe whole blood flow path and all preservative flow path is located atinlet clamp 116. From the junction, the flow path extends through tubing107 to an inlet port in the separator 108.

As shown in FIG. 9 of this description, the separator housing has anoutlet that communicates with the gap between the housing and rotor andwith concentrated red cell flow path tubing 110 for withdrawingconcentrated red cells from the separator gap. In addition, the housingincludes an outlet from the rotor that communicates with the side of themembrane facing away from the gap (for example, the interior of therotor) and communicates with plasma flow path tubing 111.

For reducing the number of leukocytes that may be present in the redcells, the disposable fluid flow circuit A optionally includes aleukocyte reduction filter 113, which may be of any suitable well knownconstruction for removing leukocytes from concentrated red cells withoutunduly causing hemolysis of red cells or reducing the number of redcells in the collected product. The concentrated red cells flow from theleukocyte reduction filter 113 through a continuation 114 of theconcentrated red cell flow path into storage container 15 which may beof any suitable plastic material compatible with red cell storage.

The reusable or durable controller module B, as shown in the FIG. 9schematic, preferably includes a hematocrit sensor 104 for detecting thehematocrit and the whole blood flowing from the whole blood container101. The hematocrit detector may be of any suitable design orconstruction but is preferably as described in U.S. Pat. No. 6,419,822,which is hereby incorporated by reference.

The durable reusable controller or control module B also includes aninlet clamp 116 which may be operated to control fluid from the wholeblood container 101 or the cell preservative container 102 or,optionally, simultaneously and proportionally from both of thecontainers 101 and 102. For controlling flow of blood into theseparator, the reusable module includes an inlet pump 106, which alsomay be of any suitable construction, and may be, for example, aperistaltic type pump which operates by progressive compression orsqueezing of the tubing 107 forming the inlet flow path into theseparator, a flexible diaphragm pump or other suitable pump. A pressuresensor 117 communicates with the inlet flow path between the pump 106and the separator 108 to determine the inlet pumping pressure. Thesensor may output to the control system to provide an alarm function inthe event of an over-pressure condition or an under-pressure conditionor both.

To control the flow rate of concentrated red cells from the separator108, the reusable module also includes an outlet pump 109 that isassociated with the outlet flow path 110, and functions in the mannersimilar to that described with respect to inlet pump 106. It also may beof any suitable construction such as a peristaltic pump, a flexiblediaphragm or other suitable pumping structure. The plasma flow path 111exiting the separator is preferably not controlled by a pump, and thevolumetric flow rate through the plasma flow path tubing is thedifference between the inlet volumetric flow rate from pump 106 and theoutlet volumetric flow rate from pump 109. Reusable module B may,however, also include a clamp 118 for controlling flow of plasma throughthe plasma flow path tubing 111.

The disposable module A may also include a plasma collection container112 in fluid communication with the plasma flow path for receivingplasma separated by the separator 108. Because the plasma passes througha porous membrane in the separator 108, the plasma that is collected incontainer 112 is largely cell free plasma and may be suitable foradministration to patients, freezing for storage or subsequentprocessing.

FIG. 10 generally shows the flow path(s) of fluid through the systemillustrated in FIG. 9. Specifically, it shows flow of whole blood fromthe single unit whole blood container 101 through the whole bloodhematocrit detector 104, to a junction in the flow path located at thebinary clamp 116. Cell preservation solution, such as a red cellpreservation solution, flows from the red cell container 102 also to thejunction at the binary clamp 116. Depending on the processing stage, thebinary clamp allows the flow of whole blood or cell preservativedownstream into the remainder of the system. Optionally, the clamp 116could be a proportional clamp to allow a selected proportionate flow ofwhole blood and red cell preservative simultaneously.

From the binary clamp 116, the whole blood or cell preservative fluidflows through the inlet pump 106 and into the separation device 108. Asexplained earlier, the separation device employs a relatively rotatinghousing and rotor, at least one of which carries a membrane throughwhich plasma is allowed to pass. In one embodiment, the membrane iscarried on the surface of the rotor and plasma passes through themembrane and through internal passage labyrinth within the rotor exitingeventually to the plasma collection container 112. When the membrane ismounted on the rotor, the device is commonly referred to a spinningmembrane separator, as shown in FIG. 10. However, it should berecognized that the membrane could potentially be mounted on the insidesurface of the housing, facing the gap between the inside surface of thehousing wall and the outer surface of the membrane, or a membrane couldbe carried on both the outer surface of the rotor and the inner surfaceof the housing so that plasma flows through membranes simultaneously,therefore potentially increasing the separation speed or performance ofthe separator 108. From the separator 108, the concentrated red cellsflow through the housing outlet communicating with the gap between rotorand housing and through the red cell flow path 110 and the outlet pump109, which controls the volumetric flow rate of the concentrated redcells.

While the hematocrit of the concentrated red cells removed fromseparator 108 may vary, it is anticipated that the hematocrit of theconcentrated red cells will be approximately 80-85%. The outlet pump 109pumps the concentrated red cells into the red cell collection container115 and, optionally, through a leukocyte reduction filter located in thered cell flow path between the pump 109 and the collection container115. The force of the pump pushing the concentrated red cells throughthe leukocyte reduction filter helps to maintain the processing timewithin a reasonable range, as compared, for example, to the time itwould be required for gravity flow of concentrated red cells through aleukocyte reduction filter in a manual setting.

The plasma separated by the separator 108, as shown in the FIG. 10,flows from the separator device, for example, from an outletcommunicating with a labyrinth of passageways within the rotor through asingle control clamp 118 and to the plasma collection container 112. Asnoted earlier, because the plasma passes through the membrane, it islargely cell free and suitable for subsequent administration topatients, freezing, and/or for the processing, such as by fractionationto obtain plasma components for use in other therapeutic products. Thesystem could also include a filter such as a leukocyte reduction filterin the plasma flow line 111 if desired.

FIG. 11 illustrates one version of a potential system employing both adisposable fluid circuit module A and a reusable or durable controllermodule B. Although shown assembled, the fluid circuit module A anddurable module B have separate and independent utility and may be usedwith other systems as well. As can be seen in FIG. 11, the disposablemodule A is conveniently mounted to the face of the reusable module B,which has associated hangars or supports, some of which may beassociated with weight scales, for supporting the various containers ofthe disposable system. The disposable module is, as indicated earlier,preferably preassembled, and pre-sterilized. The cell preservativesolution container may be pre-attached as part of the disposable systemor may be added later, such as by a sterile connection device or othersuitable attachment. The whole blood container which contains the unitof previously collected whole blood may also be pre-attached to thepre-assembled fluid circuit or attached by way of a sterile connectiondevice or other suitable attachment mechanism.

The face of the reusable module B includes, in this embodiment, aseparate solution clamp 116 a for controlling flow of cell preservationsolution from the solution container 102, which is hung from an elevatedsolution support pole. The whole blood container 101 is hung from aweight scale. The weight scale may be of conventional construction andmay provide a weight measurement signal that may be used by the controlsystem of the module B for sensing the amount of whole blood thatremains in the container and/or the amount of whole blood that has beenprocessed through the system. The disposable system includes a red cellflow path 105 that extends from the whole blood container, through thehematocrit detector 104, and through a separate whole blood clamp 116 bfor controlling flow of whole blood from the container into the system.The cell preservative solution flow path 103 and the whole blood flowpath 105 combine at a junction, such as a v-site or y-site, upstream ofthe inlet pump 106. The combined flow path extends through the inletpump and to an inlet on the separator device 108. As is visible in FIG.11, the reusable module B includes a drive unit, such as a magneticdrive unit for causing rotation of the rotor within the separatorhousing without requiring drive members or components to physicallyextend through the housing. In this arrangement, the rotor includes amagnetically coupled drive element that is rotated by the magnetic driveunit associated with the reusable module. This system is described morefully in U.S. Pat. No. 5,194,145 to Schoendrofer, incorporated byreference herein.

The concentrated red cell outlet from the separator 108 is attached tothe red cell flow path 110, which extends through outlet pump 109 and toan inlet into the optional leukocyte reduction filter 113. Filter medialocated between the inlet and outlet of the leukocyte reduction filtersubstantially removes leukocytes from the red cells. From the filteroutlet, the red cell flow path tubing 114 conveys the red cells into thered cell collection container 115.

Plasma is conducted from the plasma outlet of the separator through aplasma flow control clamp 118 and into the plasma collection container112. In a manner similar to the whole blood container, the concentratedred cell container 115 and the plasma container 112 are suspended fromweight scales which may be in electronic communication with the controlsystem of the durable or reusable module B to provide informationregarding the amount of concentrated red cells and/or plasma collectedfrom the whole blood or the rate of collection.

While this system has been illustrated with certain basic components andfeatures as described above, this description is not intended topreclude the addition of other components, such as sensors, pumps,filters or the like as may be desired. For example, it may optionally bedesired to filter plasma before it enters the plasma collectioncontainer or to omit a leukoreduction filter for red cells. Although theplasma removed from the separator 108 is largely cell free, there may bea further desire to filter the plasma for reasons of subsequentadministration or processing. The present description is not intended topreclude the possible addition of further components or the deletion ofone or more of the components described above.

Turning now to the processing of whole blood in the illustrated system,the separation process begins by priming the system. “Priming” refers tothe method by which the filter membrane is prepared (i.e., wetted) priorto use. Wetting with a fluid helps to displace air present in the matrixof the membrane prior to pressure-induced fluid flow through themembrane. Typically, a low viscosity non-biological fluid, such as acell preservation solution (red cell solution such as, Adsol® solution)is used for wetting to allow the most effective displacement of air.During the prime, fluid is removed from the cell preservation solutionbag 102 by the inlet pump 106 until the solution line 103, whole bloodline 105, inlet line 107, and spinning membrane device 108 arecompletely filled with the solution. To ensure proper priming, the inletpump 106 may move both clockwise and counterclockwise during the prime.The purpose of the solution prime is to prevent an air-blood interfacefrom forming by creating a solution-blood interface and to wet themembrane within the separation device. Each is a measure taken to reducethe hemolysis of red blood cells.

After the system is successfully primed, the cell solution flow path 103will be closed by the inlet clamp 116. The illustrated inlet clamp is abinary clamp that can close either the cell preservation solution flowpath 103 or the whole blood flow path 107. Whole blood will then bepumped through the whole blood flow path 105 and the inlet flow path 107by the inlet pump 106 into the separator 108. Inlet pump 106 flow ratescan vary from about 10 ml/min to 150 ml/min depending on desired productoutcomes for a specific procedure. As the whole blood leaves the wholeblood container 101 it will pass through the whole blood hematocritdetector 104 which will generate an estimation of the whole bloodhematocrit through IR LED reflectance measurements. Details of thehematocrit detector are explained in U.S. Pat. No. 6,419,822 (Title:Systems and methods for sensing red blood cell hematocrit), incorporatedby reference. The whole blood hematocrit value is required for aninitial control algorithm of the illustrated system, but may not beessential in other systems.

After whole blood has filled the separator 108, the system will begin todraw plasma from the separator which separates the whole blood enteringthe spinning membrane device into a red cell concentrate and virtuallycell free plasma. Packed red blood cells at approximately 80-85%hematocrit will be pumped out of the separator 108 through the red cellflow path 110 and into the red blood cell leukofilter 113 by the outletpump 109. The outlet pump forces the packed red blood cells through thered blood cell leukofilter 113 and the red cell concentrate which exitsthe red blood cell leukofilter 13 through the red blood cell line 114and into the red blood cell product bag 115 will be successfullydepleted of white blood cells and also depleted of platelets. It is alsopossible to complete a whole blood automated separation without the useof a red blood cell leukofilter 113. In this case the red blood cellleukofilter 114 would be removed from the system and the red blood cellproduct 115 would not be depleted of white blood cells or platelets.

Throughout the procedure, plasma will flow through the plasma flow path111 into the plasma bag 112 at a flow rate equal to the differencebetween the inlet pump 106 flow rate and outlet pump 109 flow rate as iscurrently done in other spinning membrane separation applications likethat applied in the Autopheresis-C® instrument sold by Fenwal, Inc. Thepressure across the membrane generated by the offset in flow rates ismonitored by the pressure sensor 117. The pressure measurements are usedto control the plasma flow rate using the algorithm described in U.S.patent application Ser. No. 13/095,633, filed Apr. 27, 2011 (Title:SYSTEMS AND METHODS OF CONTROLLING FOULING DURING A FILTRATIONPROCEDURE) hereby incorporated by reference.

The system in FIGS. 9-11 will continue to separate packed red bloodcells and plasma until the whole blood bag 101 is empty as detected byair passing through the whole blood hematocrit detector 104. At thispoint the whole blood line 105 will be closed and the cell preservativesolution line will be opened by the inlet clamp 116 to start thesolution rinse or flush. During the solution rinse, preservativesolution will be removed from the solution bag 102 and pumped into theseparator 108 by the inlet pump 106. The plasma flow path 111 is closedby the plasma clamp 118 during the solution rinse. The solution rinse isused to flush any blood remaining in the system into the red blood cellproduct container 115. The solution rinse will also increase the redblood cell product container 115 volume to the level desired for properred blood cell storage. After the solution rinse is finished theseparation of the whole blood unit is complete.

Turning to FIG. 12, a further alternative two-pump system is shown. Thisembodiment differs from that in FIG. 9 primarily in that the fluid fromthe blood cell preservative solution is added after the red blood cellshave been separated from the whole blood. More particularly, acontainer/bag 101 containing previously-collected whole blood(preferably already combined with an anticoagulant) is connected to thedisposable system A through tubing segment 107 that leads to the bloodseparator 108. Pump 106 cooperates with tubing 107 to pump whole bloodto the separator 108. Container 102 containing the red blood cellpreservative additive solution is connected to the collection container115 for the separated red blood cells through tubing 114, through whichthe separated red blood cells are also directed to container 115 throughthe leukocyte filter 114.

Sterile connection of the containers 101, 102 to the disposable systemmay be accomplished by a number of different ways. Container 102 for theadditive solution may be supplied as part of the disposable system A,and may be joined to the remainder of the disposable (aftersterilization by, e.g., gamma or E-Beam processing) during finalpackaging after the remainder of the disposable has been sterilized (by,e.g., moist heat processing). Alternatively, the container 102 may beformed integrally with the remainder of the disposable. In a furtheralternative, both the container 102 and the whole blood container 101may be separate from the remainder of the disposable and connected atthe time of use through, e.g., sterile spike connections 170, shownschematically in FIG. 10. Such spike connections preferably include a0.2 micron filter to maintain sterility.

In another aspect of this embodiment, the tubing 103 connecting theadditive solution container 102 to the leukocyte filter 62 may also becooperatively engaged by the pump 109. Specifically, pump 109 may be adual pump head that flows both the additive solution and the red bloodcells exiting the separator 108 to control the flow rate of each basedupon the inside diameter of the tubings 103 and 110.

The embodiment of FIG. 12 also utilizes an additional pressure sensor117 b to monitor the back pressure from the leukocyte filter 113. Shouldthe back pressure become excessive, as in the event of filter occlusion,the sensor will act to control the flow rate in order to ensure that thedisposable does not rupture due to excessive pressure.

III. Membrane Priming

In keeping with another aspect of the disclosure, a method for priming amembrane filter is provided by which is more likely that the maximumamount of the surface area of the filter membrane is wetted, thusmaximizing the membrane area available for filtration/separation.Specifically, when a spinning membrane filter system is primed asdescribed above, with the spinning membrane oriented so that the axis ofrotation is substantially vertical, the wetting solution enters at thetop inlet port of the spinning separator, and gravity pulls the fluidtoward the outlet at the bottom of the separator. Under suchcircumstances, the surface tension of the priming fluid will form anair-fluid interface that may move unevenly across the membrane surface,creating disruptions. The result is that certain areas of the filtermembrane may not be wetted during priming, thus increasing the potentialfor air being trapped in the membrane matrix. The unwetted area of themembrane then becomes unavailable for separation, adversely affectingthe separation efficiency of the membrane, until sufficient pressure isgenerated to displace the air.

Accordingly, a method for priming a membrane separator is provided thatmore uniformly wets the membrane surface by providing a more uniformair-fluid interface during priming. To this end, priming fluid isintroduced into the separator so that it works against the force ofgravity as the fluid-air interface advances in an upward directionacross the surface of the membrane. This helps to ensure a more uniformwetting of the membrane, as the air displaced during priming is able tomove in a single direction without being trapped as the air-fluidinterface advances across the membrane.

Thus, according to this alternate method for priming, the priming fluidis introduced into the separator through a port at the bottom of theseparator. The priming solution advances upwardly in the housing of theseparator against the force of gravity to wet the surface of themembrane, with the air being expelled from the separator through a portat the top of the separator. While this “bottom to top” priming isdescribed in the context of a spinning membrane separator, it is alsoapplicable to any type of membrane separator that requires fluid primingprior to use.

With reference to FIGS. 9 and 12, the separator 108 is orientedvertically, so that the membrane separator and housing are relativelyrotatable to one another about a generally-vertical axis, with the portfor receiving the whole blood at the top of the separator and the portsthrough which the separated RBCs and plasma exit at the bottom of theseparator. Thus, according to one way for performing this alternativepriming method, and with reference to FIGS. 1 and 2, the primingsolution may be introduced through one of the exit orifice 34 or plasmaoutlet orifice 46 of the spinning membrane separator 10, while air isexpelled through the inlet orifice 22. According to another way forperforming this alternative priming method, separator 10 may be invertedor upturned for priming, so that the exit orifice 34 and plasma outletorifice 46 are at the top of the separator 10, and the inlet orifice 22is at the bottom of the separator 10. The priming solution may then beintroduced through the inlet 22, with the fluid-air interface advancingupwardly and air being expelled through either or both of the exitorifice 34 and the plasma outlet orifice 46. After priming, theseparator 10 may be returned to its original orientation, with the inletorifice 22 at the top and the exit orifice 34 and plasma outlet orifice46 at the bottom.

A further alternative in which the “bottom to top” priming of the bloodseparator 108 described above may be used is shown in FIG. 12A. Incontrast to FIG. 12, the inlet line 107 for the whole blood connects tothe lower port of the separator 108 (to which the outlet line 110 hadbeen attached in the embodiment of FIG. 12), while the outlet line 110is connected to the port at the top of the separator 108 (to which theinlet line 107 had been attached in the embodiment of FIG. 12). To primethe system of FIG. 12A, clamp 116B is opened and pump 106 activated toflow whole blood (preferably with anticoagulant added) through the inletline 107 so that it enters the separator 108 through the port at thelower end of the housing. As the whole blood fills the separatorhousing, air is expelled through the top port, to substantiallyeliminate all air from the device, and the filter membrane is wetted.

After priming is completed, the system continues to operate as shown inFIG. 12A to separate the whole blood into plasma, received in container112, and red blood cells, received in container 115. At the end of theseparation procedure, the separator may be rinsed with additive solutionfrom container 102.

Turning to FIGS. 14 and 15, a further alternative blood separationsystem according to the present disclosure is shown. The system of FIGS.14 and 15 is similar to that of FIGS. 9, 11, and 12 except that thedurable module B includes a third pump 119 for selectively flowingadditive solution to either the separator 108 during the priming phase(as shown in FIG. 14), or to the separated red blood cells during theseparation phase (as shown in FIG. 15). The system of FIGS. 14 and 15also includes a further clamp 120 for selectively permitting orpreventing flow of fluid (separated red blood cells and additivesolution) through the leukofilter 113 and into the red blood cellcontainer 115. Prior to priming, clamp 20 could briefly remain open andpump 109 could pump residual air from container 115 and filter 113,minimizing the amount of air remaining in container 115 at the end ofthe procedure. Like FIG. 12A, the system of FIGS. 14 and 15 employsbottom to top priming of the separator 108, except using additivesolution for the priming fluid instead of whole blood. During priming ofthe system, as shown in FIG. 14, air from the disposable system A ispushed to the whole blood container 101.

During the separation phase, the system is operated as shown in FIG. 15.At the conclusion of the separation phase, additive solution is pumpedto the separator 108 (as shown in the prime phase illustrated in FIG.14) to rinse the separator.

Turning to FIG. 15A, a further alternative system is shown. The systemof FIG. 15A is like that of FIGS. 14 and 15, in that the reusablecomponent B comprises three pumps 106, 109, and 119. However, the systemof FIG. 15A is similar to that of FIG. 12A, in that the inlet line 107for the whole blood is connected to the port at the bottom of theseparator 108, while the outlet line for the separated red blood cellsis connected to the port at the top of the separator. Thus, the systemof FIG. 15A, whole blood is used for priming the system, similar to thesystem of FIG. 12A.

IV. Data Management Systems and Methods

The system described herein can also incorporate data managementsolutions. Weight scales and the addition label printing devices to thesystem would allow users to obtain product weight labels directly fromthe separation system at the completion of the procedure. Thiseliminates manual weighing and recording of data used in currentprocessing methods. The module B may include a suitable user interface,such as a touch screen, keypad or keyboard, as well as a scanner, toallow users to input information such as user donor identificationnumber, blood bank identification, fluid circuit kit numbers, lotnumbers, etc., which could also improve data management efficiency inblood manufacturing centers.

More specifically, and in accordance with another aspect of the presentdisclosure, a method is provided for automating the transfer of dataassociated with the whole blood collection container, as well as otherpertinent information, to the processing circuit used for the subsequentseparation of the whole blood and the final storage container orcontainers for such separated blood component or components. This methodis illustrated schematically in the flow chart of FIG. 29, where asource container is provided (step 122), which typically contains a unitof previously-collected whole blood, although the source container maycontain a previously-processed blood product. The source containertypically has data associated with it relating to the identification ofthe donor and the collection time, place, etc., such data preferablybeing in a machine-readable format, such as a bar code or a RFID tag.This data is then retrieved and transferred (step 124), and thenassociated with the processing circuit and final storage containers(step 126).

Turning to FIG. 30, one possible system for the use of a data managementsystem in accordance with the present disclosure is shown. A bloodcollection container 128 and a separate processing circuit 130 havingthree final storage containers 132, 134 and 136, are provided. Duringthe collection of the whole blood, donor identification information isencoded and associated with the container for the collected whole blood.This may be done by manually placing a bar code label for the donor idonto the container label, container pin, or tubing. It may also be doneby utilizing an RFID writer at the point of collection, transferring thedonor ID from a collection scale or hand-held device onto an RFID tagattached to the collection container. The use of RFID permits a greateramount of information to be managed, including such data ascontainer-type, expiration date, collection time, collection volume,nurse identification, collection site, and the like.

The automated data transfer between the collection container 128 and theprocessing kit 130/storage containers 132, 134, 136 may occur in thecontext of the sterile connection of the collection container 128 to theprocessing kit 130. For example, an electromechanical system thataccomplishes the sterile connection of the whole blood collectioncontainer to the processing kit may be used. Such a system is disclosedin U.S. Provisional Patent Application Ser. Nos. 61/578,690 and61/585,467 filed on Dec. 21, 2011 and Jan. 11, 2012, respectively, whichare incorporated herein by reference. The sterile connect device may befree standing, as shown in the above referenced provisionalapplications, or integrated with the reusable module B described above.Alternatively, the data management system may be simply associated withthe reusable module B, without a sterile connect device associatedtherewith. In any event, the sterile connection device or reusablemodule includes a programmable controller configured to automaticallyperform, or prompt the user to perform, the various steps of the datamanagement method, as described in greater detail below.

The data management system 138 incorporates a processing unit, a screen140 for providing information to the user (such as prompts andconfirmations), a touch pad 142 to permit the user to input information,and a scanner/reader 144 for retrieving and transferring informationbetween the collection container 128 and the processing kit 130. Thesystem 138 also provides for the printing of bar code labels or transferof data to one or more RFID tags associated with the processing kit.Turning now to FIG. 31, a flow chart generally illustrating the datamanagement method is shown. The method includes loading the collectionbag and processing kit onto the reusable module and/or sterile connectdevice (step 140). The data associated with the processing kit and thedata associated with the collection container is retrieved (steps 142and 144). As can be appreciated, the order in which these steps areperformed is not critical. As noted above, this data may take the formof a bar code, an RFID tag or other form, the processing kit and itsassociated collection containers have the pertinent data from thecollection container associated therewith. This may either take the formof printing bar code labels or writing data to an RFID tag (steps 146and 148). The collection container and processing kit are connected,preferably in a sterile connect procedure (step 150), such connectionoccurring at a time during the sequence of the performance of theabove-described steps.

The blood in the collection container is then processed (step 152). Theprocessing kit/storage container information is then retrieved andverified against the collection container data (steps 154 and 156).After such verification, the storage containers may be disconnected fromthe collection container (step 158).

The system of the present disclosure assists the user in performing thesteps described above in that it provides prompts and confirmations forthe various steps. For example, if the identifying information is in theform of a bar code, the system prompts the user to scan the bar code IDof the processing kit and the donor ID of the collection container. Thesystem will then print replicate bar code labels on a printer that iseither integral to the system or attached to it, with the type andquantity of the labels being determined by the type of processing kitloaded. The system then prompts the user to apply the bar code labels tothe final storage containers. After the system processes the blood intoits components, the system prompts the user to scan the final componentcontainer bar code IDs so that the system may verify correct bar codeinformation prior to detaching the storage containers from thecollection container and processing kit.

If the identifying information is associated with an RFID tag, thesystem automatically scans the RFID tag on the collection container andthen automatically reads the information on the RFID included on theprocessing kit. The system then automatically replicates the collectioncontainer information to the RFID tag or tags associated with theprocessing kit storage containers. After the system processes the bloodinto the components, according to the type of processing kit detected bythe instrument, the system will read the RFID tag on the final componentcontainers to permit verification of the identifying information priorto detaching the blood storage containers from the processing kit andcollection container.

It is contemplated that the system may employ both bar code and RFID asredundant systems, and include some or all of the steps described above,as applicable. While the bar code scanner/RFID reader is described asbeing associated with the reusable module B, it could be a dedicatedstation physically separate from the processing machine itself, thoughlinked through the data management software.

While this data management method has been described in connection withthe collection of the whole blood in a container separate from theprocessing kit and storage containers, it may equally well be used inconnection with a system or kit in which the collection container isintegral with the processing kit and its storage containers. Further,the method may be used in connection with the processing of whole blooddrawn directly from a donor, as described below, with the donoridentification data being provided by the donor, and not a collectioncontainer, or in a cell washing procedure, with the identification databeing associated with the source container.

V. Systems and Methods for Processing Whole Blood from a Donor

In accordance with another aspect of the present disclosure, thespinning membrane separator described above may be advantageously usedin the single step or “chairside” collection and separation of wholeblood into blood components. As described below, an automated wholeblood collection system is provided that separates whole blood into asingle unit of red blood cells and plasma simultaneously with thecollection of whole blood from a donor. The system is intended to be asingle pass collection system, without reinfusion back to the donor ofblood components. The system preferably comprises a disposable fluidflow circuit and a durable reusable controller that interfaces with thecircuit and controls fluid flow therethrough. The flow circuit ispreferably a single use pre-sterilized disposable fluid flow circuitthat preferably comprises red blood cell and plasma collectioncontainers, anti-coagulant and red cell additive solutions, a separatorand a fistula for providing a passageway for whole blood from the donorinto the fluid circuit. The durable controller preferably comprises amicroprocessor-controlled, electromechanical device with valving,pumping, and sensing mechanisms configured to control flow through thecircuit, as well as safety systems and alarm functions, appropriate fora whole blood collection procedure.

The method of blood collection utilizing the system comprises performinga venipuncture on a donor and the withdrawing whole blood from the donorinto the disposable circuit where it is manipulated by the instrumentand the components of the fluid circuit to result in the whole bloodbeing separated into the desired red blood cell and plasma components.The donor remains connected to the system throughout the procedure, andall fluids remain in the fluid path of the single-use kit until theprocedure is completed. As a “single pass” system, whole bloodpreferably passes through the flow circuit one time only, and no bloodcomponent is returned to the donor.

The red blood cells resulting from the collection may not necessarily beprocess leukoreduced. However, leukoreduction by filtration may beachieved with a leukoreduction filter preferably integrated to thesingle use circuit or by the use of a separate processing circuit thatis sterile-connected to the red blood cell collection container.

The instrument preferably includes an operator interface for inputtinginformation and/or displaying information such as a touch screen,keypad, mouse, keyboard, etc. A message display allows the operator tocontrol the procedure, gather information on its status, and address anyerror conditions as they may arise.

Turning to the drawings, there is seen in FIGS. 16-19 a schematicrepresentation of a whole blood automated collection system, generallydesignated 210, in accordance with the present disclosure, in differentstages or phases of operation. The system preferably includes a reusablehardware component 212 that preferably comprises pumps, clamps andpressure sensors to control fluid flow, and a single-use pre-assembledsterile disposable fluid circuit component 214 that may be mountable tothe hardware component and includes various containers/pouches, a donoraccess device or fistula, and a blood separation chamber, allinterconnected by a sterile fluid pathway, such as flexible plastictubing. The containers/pouches are typically collapsible, and made of asuitable plastic material, as is well known in the art. The material ofthe containers may differ depending on usage, and may includeplasticizer-free materials such as DEHP-free polymers, particularly, butnot exclusively, for red cell storage.

More specifically, the illustrated fluid circuit component or module 214comprises a donor access device 216 that includes a first length oftubing 218 as the draw line through which whole blood is withdrawn froma donor and introduced into the fluid circuit 214. The donor accessdevice 216 preferably comprises a needle, and particularly a small gaugeneedle (18-21 gauge) for enhanced donor comfort with a needle guard ifdesired for prevention of inadvertent needle sticks. The tubing 218communicates with a blood separation device, generally designated 220and, as described above, to introduce whole blood into the separator.

A second length of tubing 222 provides for fluid communication betweenthe separator 220 and a first container/pouch 224 for receipt of theseparated concentrated red blood cells, while a third length of tubing226 provides for fluid communication between the separator 220 and asecond container/pouch 228 for the receipt of plasma.

The fluid circuit 214 also comprises a source of anticoagulant (e.g.,CPD), which is contained in a third container 230 that communicates withthe first length of tubing 218 by means of a fourth length of tubing 232that is joined to tubing 218 by, e.g., a Y-connector. The fluid circuit214 may also include a source of preservative solution for the red bloodcells that are to be delivered to the container/pouch 224. Thepreservative solution may be contained in a separate pouch that iscommunication with the container 224. Alternatively, the container 224may be pre-filled with an amount of preservative solution adequate forthe amount of red blood cells to be received therein during thecollection procedure.

The fluid circuit 214 also includes an integral sampling system 234 forthe aseptic collection of blood samples prior to and during the donationprocess. The sampling system 234 comprises a pouch that communicateswith the first length of tubing 218 of the donor access device through afifth length of tubing 236 upstream of the connection between tubing 218and tubing 232, through which the anticoagulant is introduced. Tubing236 preferably communicates with tubing 218 through a Y-connector orsimilar device.

The durable hardware component 212 preferably comprises a first pump 238that cooperates with tubing 218 for pumping whole blood to theseparation device 220 and a second pump 240 that cooperates with thetubing 222 for transporting substantially concentrated red blood cellsfrom the separation chamber 220 to the first collection container 224.The pumps 238, 240 are preferably peristaltic or roller pumps thatinclude a rotor with one or more rollers for compressing the tubing toforce the fluid to be moved therethrough, although other suitable pumpdesigns, such as flexible diaphragm pumps, may also be used. Thehardware component also preferably includes a third pump 242 thatcooperates with tubing 232 for transporting anticoagulant to the drawline tubing 218 through which whole blood is transported to theseparator 220. The third pump 242 provides for metering the flow ofanticoagulant, and also facilitates the priming and rinsing of thesystem, as will be described below. However, the third pump 242 isoptional, and anticoagulant may be metered to the whole blood draw line218 by gravity flow, with the tubing 232 being dimensioned to provide asuitable flow rate over the duration of the collection procedure.

The hardware component 212 also preferably comprises clamps 244, 246,248 and 250 for selectively occluding and opening the tubing segments218, 232, 222, and 226, respectively. The term “clamps” is used broadlyherein, and includes any mechanism that cooperates with the flow paths,e.g., tubing segments, of the fluid circuit to selectively permit orpreclude fluid flow therethrough. The hardware component 212 alsopreferably comprises pressure sensors 252, 254 in the draw line tubing218 proximate or adjacent the needle (pressure sensor 252) and proximateor adjacent the inlet to the separator 220 (pressure sensor 254) tomonitor the inlet pressure, such as to detect a vein collapse. A weighscale (not shown) is also preferably provided for at least the firstcontainer 224 to provide feedback on the red blood cell volumecollected.

In keeping with another aspect of the disclosure, the reusable hardwarecomponent preferably comprises a programmable controller 256 foractuating the pumps and clamps and monitoring the pressure sensors andweigh scales so that the whole blood collection procedure may besubstantially automated. The controller 256 comprises a programmablemicroprocessor, and preferably includes an operator interface, such astouch screen and message display to allow the operator to enter and viewdata and control the procedure, gather information on its status, andaddress any “error” conditions that may arise.

To perform an automated collection and separation procedure with theautomated blood collection system 210 thus far disclosed, the disposablefluid circuit 214 is loaded into operating position on the reusablehardware component 212 as shown in FIG. 16 of the accompanying drawings.In the phase or stage shown in FIG. 16, the system is primed with fluidto substantially remove air and wet the filter membrane. In the primarystage, the first clamp 244 is closed so as to prevent fluidcommunication between the donor access device 216 and the bloodseparation chamber 220, and anticoagulant is pumped via pumps 240 and242 through the tubing 218, separator 212, and tubing 222 to prime thesystem. A venipuncture is then performed on the donor with the needle ofthe donor access device to admit whole blood into the tubing 218. Atthis point, the whole blood may be sampled by means of the samplingpouch 234.

Turning to FIG. 17, after priming, the first clamp 244 is opened to flowwhole blood through the tubing 218 to the blood separator 220, via pump238, to commence the collection/separation phase of the collectionprocedure. The anticoagulant continues to be metered into the draw linetubing segment 218 through tubing segment 232 by means of the third pump242. Red blood cells exit the separator 220 through tubing 222. Thefourth clamp 250 is opened so as to permit plasma to exit the separator220 and to travel through the tube 226 to the second collectioncontainer 228. The first pump 238 presents the whole blood flow to theseparator 220, with the inlet pressure being monitored by sensor 254,while the red blood cells are pumped from the separation chamber 220 bythe second pump 240. The flow differential between the first pump 238and the second pump 240 forces the separated plasma to exit theseparator 220 into the second collection container 228.

With reference to FIG. 18, when the volume of the red blood cells in thefirst collection container 224 reaches a predetermined volume (asmeasured by the weight of the first collection container 224 as detectedby the weigh scale), the weigh scale will provide the controller 256with a signal that prompts the controller to terminate the collectionprocedure by closing the first clamp 244, thus occluding the draw line218. The donor access device 216 may be withdrawn from the donor at thistime. If the system is to be rinsed, the fourth clamp 250 is closed toocclude the flow line 226 to the second collection container 228 for theplasma. The first pump 238 is deactivated while the third pump 242continues to deliver anticoagulant to the separator 220 with theanticoagulant being exhausted to the first collection container 224through the tubing segment 222.

Turning to FIG. 19, at the conclusion of the rinse cycle, the secondclamp 246 and third clamp 248 are closed, and the second pump 240 andthird pump 242 deactivated.

At this point, the first collection container 224 containing thesubstantially concentrated red blood cells may be separated from thedisposable fluid circuit 214 for storage or to facilitateleukofiltration. This may be done by simply hanging the collectioncontainer 224 and allowing gravity filtration of the red blood cellsthrough a leukoreduction filter into a final storage container. However,in accordance with another aspect of the disclosure, and as shown inFIG. 20, a third collection container 258 may be provided that is influid communication with the second collection container 224 through atubing segment 260, with the tubing segment 260 being in fluidcommunication with tubing segment 222 through a Y connector located ontubing segment 222 between the outlet of the separator 220 and thesecond pump 240. The third clamp 248 may then be opened to permit theflow of concentrated red blood cells out of the collection container224, with the second pump 240 activated and pumping in the reversedirection to force the flow of concentrated red blood cells through theleukocyte reduction filter 262 and into the collection container 258.The pressure generated by pump 240 expedites the filtration processsignificantly as compared to gravity-fed leukofiltration of red cells.

As a further alternative, leukoreduction may be performed with respectto the whole blood during the draw phase of the operation. Turning toFIGS. 21 and 22, the draw line tubing 218 may include a leukocytereduction filter 264 that is in line with the tubing 218. The filter 264is located upstream of the first pump 238 so that the pump will exert asufficient draw force on the blood to draw it through the filter 264during collection. The leukofilter 264 may be located on the tubingsegment 218 either upstream of where the anticoagulant is introducedinto the system (as shown in FIG. 21) or downstream of where theanticoagulant is introduced into the draw line 218 (as shown in FIG.22). Placement downstream of the anticoagulant junction allows the useof anticoagulant to flush any remaining whole blood from the filter 264after the draw from the donor is completed. Also, placement of aleukoreduction filter in the draw line tubing 218 eliminates the needfor a separate downstream leukoreduction filtration step, thus furtherstreamlining the blood collection process.

The automated single-pass whole blood collection system and methoddescribed herein are expected to improve blood collection centerefficiency, and decrease the operational costs, by accomplishing theseparation of whole blood into red blood cell and plasma componentswithout the need for subsequent manual operations. Further, the use ofsmaller-gauge needles in the donor access devices used with the systemshould enhance donor comfort, while the use of a draw pump allows thesystem to achieve donation times similar to typical whole bloodcollection. Additionally, by having the whole blood collectioncontrolled by microprocessor, greater opportunities for data managementare provided that are not typically found in current manual whole bloodcollection methods, including the use of integrated bar code readersand/or RFID technology, as described above.

In accordance with another aspect of the disclosure, methods, systems,and devices useful in the washing of biological cells, such as bloodcells or other blood or biological components, are described below.

VI. Systems and Methods for Cell Washing

Biological cell washing may serve several purposes. For example, cellwashing may be used to replace the liquid medium in which biologicalcells are suspended. In this case, a second liquid medium is added toreplace and/or dilute the original liquid medium. Portions of theoriginal liquid medium and the replacement liquid medium are separatedfrom the cells. Additional replacement liquid media may be added untilthe concentration of the original liquid medium is below a certainpercentage. Thereafter, the cells may be suspended in, for example, thereplacement medium.

Cell washing may also be used to concentrate or further concentratecells in a liquid medium. The cells suspended in a liquid medium arewashed, such that a portion of the liquid medium is separated andremoved from the cells.

Furthermore, cell washing may be used to remove undesired particulates,such as gross particulates or unwanted cellular material from a cellsuspension of a particular size or “purify” a desired cell suspension orother liquid.

The method, systems, and apparatus described below may be employed towash cells for any of the above-described reasons. More particularly,but without limitation, the methods, systems and apparatus describedbelow may be used to wash blood cells such as red blood cells or whiteblood cells (leukocytes), or platelets.

In one particular embodiment, a suspension including white blood cellsin a liquid culture medium may be washed to replace the liquid culturemedium with another medium, such as saline, prior to use or furtherprocessing. The cell suspension including white blood cells in a liquidculture medium is delivered and introduced into a separator, such as aspinning membrane separator. The spinning membrane separator has amembrane filter with a pore size smaller than the white blood cells. Inone embodiment, a liquid wash medium including the replacement liquidmedium, such as saline, is also added to the separator to dilute theliquid culture medium. The separator is operated such that the liquidspass through the pores of the membrane and are extracted as waste. Inthis embodiment, as the liquid is extracted, the wash medium is added,such that the resulting cell suspension includes white blood cellssuspended in the replacement liquid medium (e.g., the saline).

In another embodiment, the cell suspension may be concentrated (byremoving supernatant) and collecting the concentrated cell suspension ina container of the processing set. Replacement fluid may be introducedinto the separator, combined with the concentrated cells in thecontainer and the cells then resuspended with the replacement fluid. Ifnecessary, the resuspended cells/replacement fluid may be introducedinto the separator to further concentrate the cells, remove supernatant,and resuspend the concentrated cells with additional replacement fluid.This cycle may be repeated, as necessary.

Similar processes may be used to wash red blood cells suspended in aliquid storage medium. The cell suspension including red blood cellssuspended in a liquid storage medium may be washed to replace the liquidstorage medium with another medium, such as saline, prior to use orfurther processing. The cell suspension is delivered and introduced intoa separator, such as a spinning membrane separator. The spinningmembrane separator has a membrane filter with a pore size smaller thanthe red blood cells. In one embodiment, a wash medium, i.e., replacementliquid medium, such as saline, may also be added to the separator todilute the liquid storage medium. The separator is operated such thatthe liquid passes through the pores of the membrane and is extracted aswaste. As the liquid is extracted, the wash medium is added, such thatthe resulting cell suspension includes red blood cells suspended in thereplacement liquid medium (i.e., the saline). The wash and/orreplacement liquid may also be a storage medium that includes nutrientsand other components that allow for the long-term storage of the cells.Alternatively, in another embodiment, the red blood cells may first beconcentrated and removed to a container, as generally described above.Replacement fluid may then be combined with the red blood cells in thecontainer. The replacement fluid may be directly introduced into thecontainer, or introduced into and through the separator and then intothe container.

The systems, methods, and apparatus for cell washing described hereinutilize a disposable set that includes a separator, such as a spinningmembrane separator. The disposable set with the spinning membraneseparator is mounted onto the hardware component of the system, i.e.,separation device. The separation device includes clamps, pumps, motors,air detecting sensors, pressure transducer sensors, Hb detectors, weightscales, and a control logic/microprocessor included in a microprocessor.The control logic/microprocessor receives input data and signals fromthe operator and/or the various sensors, and controls the operation ofthe clamps, pumps and motors.

The cell suspension to be washed, i.e., cells suspended in a medium, maybe provided in a sterile, disposable source container, which isconnected, in sterile fashion, to the disposable set. A wash medium,such as saline or other suitable liquid, is also connected in sterilefashion or pre-attached to the disposable set. The control logic of thedevice operates the clamps and pumps to circulate the cell suspensionthrough the tubing of the disposable set to the (spinning membrane)separator. The separation device, through its control system, alsodirects the wash solution through the tubing of the disposable set tothe spinning membrane separator. The cell suspension and the washsolution may be mixed within the spinning membrane separator, may bemixed prior to entering the spinning membrane separator, or may becombined in a container after the cell suspension has been concentrated.Within the spinning membrane separator, the suspension medium isseparated from the cells suspended therein. The suspension medium andremaining wash medium (if the suspension medium and wash medium havebeen combined) exits through a waste port, while the cells pass througha separate exit port.

If further washing and dilution is necessary, the washed cells may bere-circulated through the separator with an additional volume of thewash solution. In one embodiment, the cells that are to be “re-washed”may be transferred to one or more in-process containers, as will bedescribed below. The control logic of the device operates clamps andpumps to circulate the cell suspension from the in-process containerthrough tubing to an inlet of the spinning membrane separator or to aninlet of a second spinning membrane separator. Further wash medium isadded, and the process repeats until an acceptable amount orconcentration of the cells is achieved. The final cell suspensioncontaining the cells is preferably collected in a final productcontainer.

In accordance with the present disclosure, FIGS. 23-25 show exemplarysystems useful in the washing of biological cells, such as, but notlimited to, red blood cells and white blood cells. As noted above, thespecific embodiments disclosed are intended to be exemplary andnon-limiting. Thus, in one embodiment, the system described hereinincludes a disposable set 300 (FIG. 23 or 24) and hardware component ordevice 400 (FIG. 25). It will be appreciated that the disposableprocessing sets 300 shown in both FIGS. 23 and 24 are, in many respects,identical and common reference numerals are used in both FIGS. 23 and 24to identify identical or similar elements of the disposable processingsets. To the extent that disposable processing sets differ in structureor in their use, such differences are discussed below. Disposable set300 is mounted onto device 400 (FIG. 25), which is described in greaterdetail below.

As shown in FIGS. 23-24, separator 301 is integrated into the exemplarydisposable set 300. Additionally, as will be described in greater detailbelow, disposable set 300 includes tubing, Y-connectors, in-processbag(s), sample pouch(es), final product bag(s), waste bag(s), andsterile filter(s).

The cell suspension to be washed is typically provided in a sourcecontainer 302, shown in FIGS. 23 and 24 as disconnected from thedisposable set. As noted above, source container 302 may be attached (insterile fashion) at the time of use. Source container 302 has one ormore receiving ports 303, 305, one of which may be adapted to receivespike connector 304 (FIG. 23) of disposable set 300. More particularly,source container 302 is connected to the disposable set 300 via thespike connector 304, which is connectable to access port 303. Morepreferably, however, source containers (and the fluid therein) may befree of a spike connector (as shown in FIG. 24) and accessed in asterile manner by employing sterile docking devices, such as theBioWelder, available from Sartorius AG, or the SCD IIB Tubing Welder,available from Terumo Medical Corporation. A second access port 305 mayalso be provided for extracting fluid from the source bag 302.

As further shown in FIGS. 23-24, tubing segment 306 may optionallyinclude a sampling sub-unit at branched-connector 308. One branch ofbranched-connector 308 may include a flow path 310 leading to samplepouch or site 312. Sample pouch or site 312 allows for the collection ofa sample of the incoming source fluid. Flow to the sample pouch or site312 is typically controlled by clamp 314. The other branch ofbranched-connector 308 is connected to tubing 316. Tubing 316 isconnected to further downstream branched-connector 318.Branched-connector 318 communicates with tubing 316 and tubing 320,which provides a fluid flow path from in-process bag 322, described ingreater detail below. Tubing segment 324 extends from one of the portsof branched-connector 318 and is joined to a port of further downstreambranched-connector 326. A separate flow path defined by tubing 328 isalso connected to a port of branched-connector 326. Tubing 328 mayinclude an in-line sterile barrier filter 330 for filtering anyparticulate from a fluid before it enters the flow path leading tosecond branched-connector 326 and, ultimately separator 301.

In accordance with the system disclosed herein, a wash solution may beattached (or pre-attached) to set 300. As shown in FIGS. 23 and 24,tubing 332 (defining a flow path) preferably includes spike connector334 at its end. Spike connector 334 is provided to establish flowcommunication with a container of a wash fluid, such as a disposable bagcontaining saline or other solution (not shown). The wash medium orfluid flows from the wash fluid source, through the second spikeconnector 334, through tubing segment 332, where it is filtered by thesterile barrier filter 330 described above, and then passes throughtubing 328 to the input of the branched-connector 326 described above.

Tubing segment 336 defines a flow path connected at one end to a port ofbranched-connector 326 and to an inlet port of the separator 301.Preferably, in accordance with the present disclosure, separator 301 isa spinning membrane separator of the type described above.

As shown in FIGS. 23, 24 and 25, the spinning membrane separator 301 hasat least two outlet ports. Outlet 646 of separator 301 receives thewaste from the wash (i.e., the diluted suspension medium) and isconnected to tubing 338, which defines a flow path to waste productcontainer 340. The waste product container includes a further connectionport 341 for sampling or withdrawing the waste from within the productcontainer.

Separator 301 preferably includes a second outlet 648 that is connectedto tubing segment 342. The other end of tubing segment 342 is connectedto branched-connector 344, which branches into and defines a flow pathto one or more in-process containers 322 and a flow path to a finalproduct container 350. The final product container 350 may also includea sample pouch 352 (see FIG. 23) and an access port or luer connector354. Sample pouch 352, shown with a pre-attached tube holder 352 in FIG.23, allows for sample collection of the final product. Flow control tothe sample pouch 352 is preferably controlled by clamp 356. The flowpath through the access port 354 is controlled by clamp 358.

Turning now to the method of washing using the kit 300 of FIGS. 23 and24, the disposable set 300 is first mounted onto panel 401 of theseparation device (i.e., hardware) 400, shown in FIG. 25. Device 400includes peristaltic pumps, clamps, and sensors, which control the flowthrough the disposable set. More specifically, control of the pumps,clamps and the like is provided by a software-drivenmicroprocessor/controller of device 400. Tubing segments 362, 366 and368 (shown in FIG. 23) are selectively mated with peristaltic pumps 402,404, or 406 (shown in FIG. 25). (Waste line pump segment 368 may berelocated to separator outlet line 342, if desired.) Once the disposableset 300 is mounted onto the control panel 401 of device 400, the cellsuspension in product bag 302 is attached, as previously described, byspike connector 304 or by sterile connection. A wash medium provided ina container (not shown) is likewise attached. In accordance with theoperation of device 400, clamp 360 is opened and allows the cellsuspension to flow from the product container 302.

Flow of the cell suspension is advanced by the action of peristalticpump through the tubing 324 designated by the pump segment 362 and intothe spinning membrane separator 301. Similarly, wash medium is advancedby the action of peristaltic pumps through the length of tubing 328designated by the pump segment 366 with valves 362 and 364 in an openposition. The wash medium flows through tubing 332, the sterile barrierfilter 330, tubing 328, Y-connector 326, and into the spinning membraneseparator 301. The wash medium and the cell suspension may besequentially introduced into spinning membrane separator 301, allowingfor mixing of the suspension and wash solution to occur within thechamber (gap) of separator 301 or in in-process container 322, asdescribed below. Alternatively, the wash medium and cell suspension maybe combined prior to introduction into separator 301 at (for example)the second branched-connector 326.

In yet a further alternative, cell suspension may first be introducedfrom source container 302 into separator 301, as generally describedabove. Cell suspension is concentrated within separator 301, allowingsupernatant to pass through membrane, through outlet port 382, to wasteproduct container 340. Concentrated cells exit separator 301 throughport 384 and are directed to in-process container 322.

Once separation of concentrated cells from supernatant of the cellsuspension is completed, replacement fluid is introduced from areplacement fluid container (not shown) into separator 301 (to flush outany residual cells) and is likewise directed through port 384 toin-process container 322. The concentrated cells are resuspended in thereplacement fluid within in-process container 322, as shown in FIG. 23.If additional washing is desired or required, the system may bepre-programmed or otherwise controlled to (re)introduce the resuspendedcells/replacement fluid into separator 301, wherein the separation ofconcentrated cells from supernatant is repeated. The final cell productis collected in final product container 350, where it may be resuspendedwith additional replacement fluid.

Regardless of the sequence of cell suspension/wash solution introductionor the disposable set used, the spinning action of the device causescells to separate from the remainder of the fluid in which it wassuspended and/or from the wash solution. Preferably, the supernatant andthe wash solution pass through the membrane while the desired cells areconcentrated within the chamber of the separator. The waste resultingfrom the separation, which includes wash medium and supernatant medium,exits port 382 and flows through tubing 338 to waste product container340. The flow of waste is controlled by peristaltic pump through aportion of tubing 338 designated by the pump segment 368 to the wasteproduct bag 340.

As described above, the concentrated and separated cell suspension exitsthe second outlet 384 of the spinning membrane separator 301. If nofurther washing is required, the control system closes clamp 370 andopens clamp 372. The closing of clamp 370 prevents the washed cellsuspension from flowing through the tubing 346 and directs it throughtubing 348 to the final product bag 350. The final product container 350has an input for receiving the separated and washed cell suspension. Thefinal product container 354 is connected to a weight sensor 374. Theseparation device measures the weight 374 of the container to determinewhether the volume of the collected cells in final product container 350is in the acceptable range and, therefore, whether the washing cycle iscomplete.

If further washing of the separated cell suspension is desired orrequired, the control system of separation device closes clamp 372 andclamp 376 and opens clamp 370. The closing of clamp 372 prevents thecell suspension from flowing through the tubing 348 and directs itthrough tubing 346 to the in-process bag 322. The in-process bag 322 hasan inlet for receiving the separated cell suspension. The in-process bag322 is connected to a weight sensor 378. The control system of theseparation device determines the weight as sensed by weight sensor todetermine whether enough of separated cell suspension is present in thein-process bag 322 to conduct another wash cycle. If it is determinedthat enough of the suspension is present, and further washing isdesired, the control system of the separator device opens clamp 376 toopen and directs the diluted and separated cell suspension through theoutput of the in-process bag 322, through tubing 320, intobranched-connector 318, and through an air detector sensor 380. The airdetector sensor 380 detects air in the cell suspension which passesthrough tubing 324. The control and operation device measures thereadings from air detector sensor 380 and determines the furtherprocesses to be taken.

The separated cell suspension which includes cells suspended in dilutedsuspension medium is then passed through the washing process again, asdescribed above. The wash process may be repeated as many times asdesired and preferably until the diluted and separated cell suspensionhas an acceptable remaining concentration of suspension medium. Thefinal diluted and separated cell suspension is collected in the finalproduct bag 350.

Alternatively, rather than repeatedly processing the fluid through asingle in-process container, a “batch-type” processing procedure may befollowed by using two or more in-process containers 322 (in combinationwith final product container 350).

The disposable processing set 300 of FIG. 24 is particularly well suitedfor such “batch-type” processing. In accordance with a cell washingprocedure using disposable set 300 of FIG. 24, cells initially separatedfrom the original suspension medium are removed from separator 301 andintroduced into one of the in-process containers 322 a. Replacementfluid is introduced into container 322 a and the cells resuspended.Resuspended cells in container 322 a may then be introduced intoseparator 301 wherein they are separated from the supernatant.Concentrated cells exit through outlet 648 in separator 301 and areintroduced into a fresh (second) in-process container 322 b. Additionalreplacement fluid may be introduced into in-process container 322 b, andthe process repeated, if necessary, with a further fresh (third)in-process container (not shown). The final cell product is thencollected in final product container 350, as described above.

In accordance with the “batch-type” cell washing method described above,tubing segments 370 a, 370 b and 320 a, 320 b may be associated withclamps (not shown) to control flow to and from multiple in-processcontainers 322 a and 322 b. Thus, for example, a clamp on line 370 awould be open, while a clamp on line 370 b would be closed so that cellsexiting separator 301 are directed to (first) in-process container 322a.

For additional washing, cells resuspended in the fresh replacement fluidfrom container 322 a are introduced into separator 301 where the cellsare separated from the supernatant, as previously described. The controlsystem of device 400 closes the clamp (not shown in FIG. 24) on tubingsegment 370 a and opens the clamp (not shown in FIG. 24) on tubingsegment 370 b to allow cells to flow into fresh (second) in-processcontainer 322 b. After the final wash, clamps (not shown) on segments370 a, 370 b, etc., are closed and clamp 372 (as shown, for example, inFIG. 23) is opened to allow collection of the final product in container350.

FIG. 24 shows the front panel 401 of separation device 400; i.e., thehardware, which includes peristaltic pumps 402, 404 and 406. Asdescribed above, pump segments 362, 364 and 368 from the disposable setare selectively associated with peristaltic pumps 402, 404, and 406. Theperistaltic pumps articulate with the fluid set of FIG. 23 at the pumpsegments 362, 364 and 368 and advance the cell suspension within thedisposable set, as will be understood by those of skill in the art. Thecontrol and operation device 400 also includes clamps 410, 412, 414.Clamps 410, 412, 414, and 416 are used to control the flow of the cellsuspension through different segments of the disposable set, asdescribed above.

Device 400 also includes several sensors to measure various conditions.The output of the sensors is utilized by device 400 to operate the washcycle. One or more pressure transducer sensor(s) 426 may be provided ondevice 400 and may be associated with disposable set 300 at certainpoints to monitor the pressure during a procedure. Pressure transducer426 may be integrated into an in-line pressure monitoring site (at, forexample, tubing segment 336), to monitor pressure inside separator 301.Air detector 438 sensor may also be associated with the disposable set300, as necessary. Air detector 438 is optional and may be provided todetect the location of fluid/air interfaces.

Device 400 includes weight scales 440, 442, 444, and 446 from which thefinal bag, in-process bag, cell suspension bag, and any additional bag,respectively, may depend and be weighed. The weights of the bags aremonitored by weight sensors and recorded during a washing procedure.From measurements of the weight sensors, the device determines whethereach bag is empty, partially full, or full and controls the componentsof the control and operation device 200, such as the peristaltic pumpsand clamps 410, 412, 414, 416, 418, 420, 422, and 424.

Device 400 includes at least one drive unit or “spinner” 448, whichcauses the indirect driving of the spinning membrane separator 301.Spinner 448 may consist of a drive motor connected and operated bydevice 400, coupled to turn an annular magnetic drive member includingat least a pair of permanent magnets. As the annular drive member isrotated, magnetic attraction between corresponding magnets within thehousing of the spinning membrane separator cause the spinner within thehousing of the spinning membrane separator to rotate.

FIGS. 26-28 diagrammatically set forth the method of cell washing asdisclosed herein. The steps described below are preformed by thesoftware driven microprocessing unit of device 400 with certain stepsperformed by the operator, as noted. Turning first to FIG. 26, thedevice is switched on at step 500. The device conducts self-calibrationchecks 502, including the checking of the peristaltic pumps, clamps, andsensors. Device 400 then prompts the user to enter selected proceduralparameters (step 504), such as the washing procedure to be performed,the amount of cell suspension to be washed, the number of washings totake place, etc. The operator may then select and enter the proceduralparameters for the wash procedure (step 506).

The device (through the controller) confirms the parameter entry 506 andthen prompts the operator to load (step 510) the disposable set. Theoperator then loads the disposable set (step 512) onto the panel ofdevice 400. After installation of the disposable set, the deviceconfirms installation as shown in (step 514).

After the disposable set is mounted, the device automatically checks todetermine whether the disposable set is properly installed (step 516).After the device determines that the disposable set is properlyinstalled, the controller prompts the operator to connect the cellsuspension and wash medium (step 518). The operator then connects thewash medium (such as, but not limited to saline) (step 520) to thedisposable set via a spike connector, as previously described. Theoperator then connects the cell suspension within a product bag (step522) to the disposable set via a spike connector.

As shown in FIG. 27, after the cell suspension and wash medium areconnected to the disposable set, the operator confirms that thesolutions are connected (step 524). The device prompts the operator totake a cell suspension sample (step 526). The operator or the devicethen opens sample pouch clamp 528 to introduce fluid into the samplepouch (step 546). Once the sample pouch is filled, it is then sealed andremoved (542) from the disposable set. The operator confirms (step 544)that a sample has been taken. Following the removal of the sample pouch,the disposable set is primed (step 546) for the wash process.

The controller of separation device then commences the wash process. Thecell suspension to be washed is transferred from its container (e.g.,302 of FIG. 23) through the disposable set to the spinning membraneseparator 301. Likewise, the wash medium is transferred from its source,through the disposable set to the spinning membrane separator 301. In apreferred embodiment, the original cells of the cell suspension areconcentrated and/or collected in either an in-process bag (for furtherprocessing) or collected in a final product bag which is subsequentlyremoved from the disposable set. If (further) washing or diluting of thecell suspension is necessary, the cell suspension in the in-process bagmay be washed (a second time) with the same or different wash mediumfollowing the process outlined above. Prior to the conclusion of eachwash cycle, the cell suspension volume or weight is measured andrecorded (step 550). When the concentration of the cells to wash mediumreaches an acceptable level the final product bag is filled.

As shown in FIG. 28, once the desired volume of the final product iscollected, the control and operation device prompts the operator tosample and seal the final product bag (step 552). A sample pouch isattached to the final product bag. The operator then seals and removesfrom the disposable set the washed cell suspension in the final productbag (step 552). The final product bag is then agitated (step 556). Theoperator opens the sample pouch by removing a clamp (step 558). Thesample pouch is allowed to fill (step 560). Once the sample bag isfilled, the clamp is closed and the sample pouch is sealed and removed(step 562). The operator then seals the disposable set lines (step 564)and confirms that the product bag has been sealed and removed, a samplepouch has been filled and removed, and that the disposable set lineshave been sealed (step 566). The control and operation device thenprompts the operator to remove the disposable set, as shown in step 568.The operator then removes and discards the disposable set, as shown instep 570.

Thus, an improved spinning membrane separator and methods and systemsfor using such a spinning membrane are disclosed. The descriptionprovided above is intended for illustrative purposes only, and is notintended to limit the scope of the disclosure to any specific method,system, or apparatus or device described herein.

The invention claimed is:
 1. A method for wetting a membrane in aspinning membrane separator in which the separator comprises a housingwith a top and a bottom, at least one port adjacent each of the top andthe bottom of the housing, the membrane being configured to spin about agenerally vertically-oriented axis, the membrane having a surfacethrough which separation occurs being oriented substantially vertically,with a gap being defined between the housing and the membrane, themethod comprising: introducing a priming solution through the port atthe bottom of the housing into the gap; flowing additional primingsolution through the port at the bottom of the housing into the gap sothat a priming solution-air interface is formed in the gap between thehousing and the vertically-oriented surface of the membrane such thatthe interface advances upwardly through the housing and vertically alongthe membrane surface so that the only pressure to which the primingsolution in the gap is subjected is due to gravity to wet the membraneand to simultaneously displace air within the housing and expel the airthrough the port at the top of the housing; and continuing to flowadditional priming solution through the port at the bottom of thehousing into the gap until the fluid-air interface has advancedvertically across the entire surface of the membrane.
 2. The method ofclaim 1 wherein the priming solution comprises a low-viscositynon-biological fluid.
 3. A method of claim 1 wherein the primingsolution comprises whole blood.
 4. A method for wetting the membrane ofa membrane separator in which the separator comprises a housing with atop and a bottom, with at least one port adjacent each of the top andthe bottom of the housing, with the membrane supported therein, themembrane having a surface through which separation occurs being orientedsubstantially vertically, with a gap being defined between the housingand the membrane, the method comprising: introducing a priming fluidthrough the port at the bottom of the housing into the gap; flowingadditional priming fluid through the port at the bottom of the housinginto the gap so that a priming fluid-air interface is formed in the gapbetween the housing and the vertically-oriented surface of the membranesuch that the interface advances upwardly through the housing andvertically along the membrane surface so that the only pressure to whichthe priming solution in the gap is subjected is due to gravity to wetthe membrane and to simultaneously displace air within the housing andexpel air through the port at the top of the housing; and continuing toflow additional priming fluid through the port at the bottom of thehousing into the gap until the priming fluid-air interface is advancedacross the entire surface of the membrane.
 5. The method of claim 4wherein the priming solution comprises a low-viscosity non-biologicalfluid.
 6. A method of claim 4 wherein the priming solution compriseswhole blood.
 7. The method of claim 1 further comprising manuallyinverting the spinning membrane separator from an original orientationto position the port through which priming solution is introduced intothe gap at the bottom of the separator and, after wetting the membrane,returning the spinning membrane separator to the original orientation.8. The method of claim 4 further comprising manually inverting thespinning membrane separator from an original orientation to position theport through which priming solution is introduced into the gap at thebottom of the separator and, after wetting the membrane, returning thespinning membrane separator to the original orientation.